CS302 Solved Current Papers Fall 2021 by Adil Alvi

CS302 CURRENT PAPERS FALL 2021

Q1. Explain ISTYPE statement to specifying active-high or active-low Registered Mode?

X PIN 22 ISTYPE ‘reg.buffer; Z PIN 20 ISTYPE ‘reg.invert’; Figure 35.5b ISTYPE statement to specifying active-high or active-low Registered Mode Output

Q2. Names of volatile memory?

Volatile memory is computer memory that requires power to maintain the stored information. Most modern semiconductor volatile memory is either Static RAM or dynamic RAM.

Q3. Types of edge-triggered flip-flops?

Three different types of edge-triggered flip-flops are generally used in digital logic circuits. S-R edge-triggered flip-flop D edge-triggered flip-flop J-k edge-triggered flip-flop Each flip-flop has two variations, that is, it is either positive edge-triggered or negative edge Triggered.

Q4. What is Mod-n Counters?

The term Mod represents the Modulus of the counter which is the total number of unique states through which the counter will sequence through. A 3-bit Asynchronous counter can count up from 0 to 7 or count down from 7 to 0. The 3-bit counter has 8 different states represented by the 8 outputs 0 to 7.

Q5. Difference between SRAM and DRAM?

The architectural difference between the two is that DRAM uses transistors and capacitors in an array of repeating circuits (where each circuit is one bit), whereas SRAM uses several transistors in a circuit to form one bit.

Q6. Applications of shift register?

Shift register is used as Parallel to serial converter, which converts the parallel data into serial data. Shift register is used as Serial to parallel converter, which converts the serial data into parallel data.

Q7. What is Memory Signals and Basic Operations on Memory?

Two basic operations are performed on memories, that is, reading of information from the memory and writing of data to the memory. To support the two read and write operations memories provide several signals

Q8. Two names of D/A converter?

Digital binary signals are converted into analogue signals using Digital to Analogue Converters. Generally two types of D/A Converters are used, the Binary-Weighted-Input D/A Converter and R/2R Ladder D/A Converter.

Q9. How many clock pulse required entered 4 bit data into parallel in parallel output register?

The register has parallel inputs and parallel outputs. Data is entered in parallel by applying a single clock pulse. Data is latched by the flip-flops on the clock transition and is available in parallel form at the flip-flop outputs.

Q10. What is FLASH Memory Operations?

FLASH Memory operations are classified into

• Programming Operation
• Read Operation
• Erase Operation

Q11. CS, OE and W stand for?

The read and write operations are controlled through the three signals W, CS and OE.

1. Chip Select (CS) signal analog. 2) Output Enable (OE) signal. 3) Write (W) signal analog.

Q12. How many flip-flop are required to make a mod-32 binary counter?

For a mod N counter, the number of flip-flops that are required is less than or equal to 2 to the power 'n', where n is a positive integer, i.e. N ≤ 2ⁿ. Therefore, for a mod 32 counter, it can be calculated as:- 32 = 2⁵, where n = 5 So, 5 flip-flops are required to make a mod-32 binary counter.

Q13. How many bit memory in 16k?

Transcribed image text: 3-1 the dimensions of a memory are 16K words by 32 bits.

Q14. How can calculate the frequency of an unknown signal?

The frequency of a particular event is accomplished by counting the number of times that event occurs within a specific time interval, then dividing the count by the length of the time interval.

Q15. Explain J-k flip flop of race condition?

Race Around Condition In JK Flip-flop – For J-K flip-flop, if J=K=1, and if clk=1 for a long period of time, then Q output will toggle as long as CLK is high, which makes the output of the flip-flop unstable or uncertain. This problem is called race around condition in J-K flip-flop.

Q16. Types of DRAM?

DRAM stand for Dynamic RAM. There are two main types of DRAM packaging: single inline memory module (SIMM) and dual inline memory module (DIMM).

Q17. Boolean expressions of latch SR1?

The Boolean expressions that set the latch SR1 is REQ1+FLOOR1.DIR +OPEN. DIR .

Q18. What is Flash memory Row/Colum MOS?

The FLASH Memory array is arranged in the form of rows and columns. The row line is connected to the Control Gate of each MOS transistor which implements a single bit storage cell.

Q19. Explain Sample and Hold Operation?

In electronics, a sample and hold (also known as sample and follow) circuit is an analog device that samples (captures, takes) the voltage of a continuously varying analog signal and holds (locks, freezes) its value at a constant level for a specified minimum period of time.

Q20. Difference between latches and flip flop?

Both latches and flip-flops are circuit elements whose output depends not only on the current inputs, but also on previous inputs and outputs. The difference between a latch and a flip-flop is that a latch does not have a clock signal, whereas a flip-flop always does.

Q21. Types of Analogue to Digital converters?

3 types of Analogue to Digital converters: Flash Analogue-to Digital Converter Dual-Slope Analogue to Digital Converter Successive –approximation analogue to digital converter

Q22. What is d flip-flop latch gate operations?

The D flip-flop is an edge triggered device which transfers input data to Q on clock rising or falling edge. Data Latches are level sensitive devices such as the data latch and the transparent latch.

Q23. Name 2 RAM chip?

There are two main types of RAM: Dynamic RAM (DRAM) and Static RAM (SRAM). DRAM (pronounced DEE-RAM), is widely used as a computer's main memory.

Q24. Difference between state assignment and state reduction?

The process of eliminating the equivalent or redundant states from a state table/diagram is known as state reduction while State Assignment is a binary encoding used to represent. States of a sequential machine in its digital circuit. Implementation

Q25. Write I/O of Traffic signal?

The inputs are the NSSR: EWSR: LTIME: The outputs are the nsgrn: nsyel: nsred:

Q26. Difference between Johnson and ring counter?

Like a ring counter a Johnson counter is a shift register fed back on its' self. It requires half the stages of a comparable ring counter for a given division ratio. The difference between a ring counter and a Johnson counter is which output of the last stage is fed back (Q or Q').

Q27. Write name of first and second floor?

The number of latches used to store the external inputs can be reduced to two if the REQ1, FLOOR1 and OPEN button outputs (pressed when elevator is on the first floor) are Stored on one latch and the REQ2, FLOOR2 and OPEN button outputs pressed when elevator Is on the second floor) are stored on the second latch.